shipman



In all the arrangements described the restraint upon the member whose start is to be delayed, as armature 1, is overcome by very small movement ofthe thermo-actuated means, as 23 or 23a.

Movement of the member. or armature 4 may be utilized for any suitable purpose as, for example, actuating the latch or other restraining means of an electric switch, such for example as an automatic magentic cirouit breaker of which the magnet M may be the over-load magnet, or one responsive to rise in line voltage, or to any other desired electrical condition.

In the example illustrated, however, the member 4 is the armature of the electro-magnetic relay controlling or actuating the movable contacts 30 and 31, electrically connected to each other and carried by the armature 4, and adapted to engage and bridge co-acting stationary relay contacts 32 included in any circuit to be controlled, as for example in the circuit of the electromagnet utilized to control the restraining means or latch of an electric switch or circuit breaker.

What I claim is:

1. The combination with a movable member comprising a magnetizable element, of current-controlled means for exerting a force thereon to move it, means for restraining said member, heat responsive means for transmitting force to free said member from said restraining means, and heat responsive means compensating for .the efiect of changes of temperature of atmosphere upon said first named heat responsive means.

2. The combination with a magnet winding, of a movable magnetizable member coacting therewith, means dependent uponthe effect of said winding for restraining said member against movement, heat responsive means for freeing said movable member from said restraining means, and electrical means for applying heat to said heat responsive means.

applying heat to said heat responsive means, and heat responslve means for'compensatmg.-

for the efi'ect uponsaid first named heat :33:- sponsive means of clfanges of temperature of the atmosphere. v I L 4. The combination 'withfaniagnet winding, o'fa movable magnetizable member co-' acting therewith, means for restraining said movable member comprising a relatively stationary member between which and said movable member there is effected magnetic attraction, and heat responsive means for separating said members from each other.

5. The combination with a magnet'winding, of a movable magnetizable member coacting therewith, means for restraining said member against movement, and heat re sponsive means for freeing said member from said restraining means comprising an expansible chamber,a member actuated in response to expansion of said chamber, and a member actuated by said last named member for freeing said movable magnetizable member.

6. The combination with a magnet winding, of a movable magnetizable member coacting therewith, means for restraining said member against movement, and heat responsive means for freeing said member from said restraining means comprising an expansible chamber, a member actuated in response to expansion of said chamber, a member actuated by said last named member for freeing said movable magnetizable member, and .electrical means for applying heat to said chamber.

7. The combination with a magnet winding, of a movable 'inagnetizable member coacting therewith, means for restraining said member against movement, and heat responsive means for freeing said member from said restraining means comprising an expansible chamber, a member actuated in response to expansion of said chamber, a member actuated by said last named member for freeing said movable magnetizable member, and electrical means energized concurrently with said winding for applying heat to said chamber.

8. The combination with a magnet winding, of a movable magnetizable member coacting therewith, means for restraining said member against movement, and means for freeing said member from said restraining means comprising a plurality of expansible chambers, a member pivoted to a movable wall of each of said chambers for freeing said movable magnetizable member, said chambers subjected tochanges of temperature of the atmosphere, and electrical means energized concurrently with said winding for ap plying heat to one of said chambers.

9. The combinationwith a magnet winding, of a movable magnetizable member coact-ing therewith, and means for delaying start of said movable member comprising a pivoted .to movable walls of said chambers, a. third. member actuated by said second named memberFfOr actuating said movable magnetizable'memberto start it, said chambers subjected to varying temperatures of the atmosphere, and electrical means energized concurrently'with said winding for applying heat to one of said chambers.

10. The combination with a magnet winding, of a movable magnetizable member coacting therewith, means for restraining said member against movement, and means for plurality of expansible chambers, a member March 8, 1932. c, Q; sHlPMAN 1,848,669

PITMAN COUNTERBALANCE Filed Sept. 30, 1950 FIGI HARLES C. SHIPMAN INVENTOR TTORNE Y 

